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UL valve seat width

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bobul

Posts: 38

Joined: Wed Sep 08, 2004 12:01 am

Location: Finland

Post Thu Feb 15, 2007 12:31 am

UL valve seat width

What is the proper valve seat width in big flat cylinders?

I have read all my books and also done some search here...
And all I found was confligting information.

original width information found was 0.15625" 45deg angle(pretty wide)
and Palmer book tells to narrow to 0.0625" (suprisingly narrow)

basic aircooled OHV engine seats are around 0.09"..but this is flathead.

Any opinions why this much difference in information? Or is this only
result of 60 year development and people still can't agree?

My old seats seems to be on narrow side,,but needs resurfasing.
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panic

Post Thu Feb 15, 2007 7:42 am

Last edited by panic on Fri Feb 23, 2007 5:24 pm, edited 1 time in total.
<<

bobul

Posts: 38

Joined: Wed Sep 08, 2004 12:01 am

Location: Finland

Post Thu Feb 15, 2007 11:25 am

Thanks for fast reply/correction. Exhaust is critical for contact but so is the seat pressure.
In intake I consider 0.08" - 0.09" enough for width.

Normal street use is what they get.
<<

panic

Post Thu Feb 15, 2007 3:45 pm

Last edited by panic on Fri Feb 23, 2007 5:24 pm, edited 1 time in total.

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